Those bands are probably various APP fragments. They can usually range from 50 do 130 kDa. Antibody clone 6E10 reacts to the abnormally processed isoforms of Aβ, as well as various forms of APP.

Looking at your gel I would suggest that those other bands are just immunopositive products of proteolytic degradation of your target protein. Try to use protease inhibitor cocktail at the stage of your extractions / lysis of your cells or tissue.

Hi Viktor,

I used protease inhibitor in my cocktail while lysing the tissue. 

I don't think those APP bands are due to target protein degradation, and you cannnot use protease inhibitor to fix this. The gene coding for APP contains 18 exons; several alternative splicing isoforms of APP range in length from 365 to 770 amino acids. Those isoforms are not degradation byproducts during sample preparation, those are alternatively spliced APPs.

I detected the APP level by Western blotting using primary antibody of APP (abcam), I have not found any redundant band in the membrane of PVDF. Thus, the other bands that occurred in your results may be caused by the degradation of proteins.

I suppose that the other bands are aspecific signals, because they are going in the same direction, contrary to the specific band of APP. I don't know this antibody, but you can try to use 5% milk for blocking. 

Hi Ramesh, You did not specify what the samples are. The bands you labelled as APP and Abeta are what the expected bands. These are detected only in the last 3 lanes (APP transgenic mice?). My advice would be to use APP KO mouse brain lysate as a negative control. The 70-50 kDa bands may just be due to non-specific reactivity of your secondary antibody (use blocking buffer to dilute the secondary ab).

Hi Evin

Thank you for your response about my query.  First three lanes were WT, second three lines were DRP1 and last three lanes were APP transgenic mice and you are true about this. I  did dilution in 1:5000 dilution anti mouse HRP.  Can you sugesst dilution whether should I increase or decrease because if I decrease I am looking even more non specific bands.  

Thank you you again every one for their responses

sincerly

ramesh 

Hi,

Have a look on below mentioned chapter, it may prove helpful.

http://link.springer.com/protocol/10.1007/978-1-60761-744-0_4

Thank you Shafiq for the protocol book